1.
a) 165/18=9.17
b) 615/18=34.17
In scale factor, the Coliseum was 9.17 inches tall and 34.17 inches long.

2.
a) 32/18=1.77 inches
b) 42/18=2.33 inches
On the model, each floor is 1.77 inches long and 2.33 inches tall.

3.
a) 278/18=15.44 inches
b) 180/18=10 inches
15/18=0.83 inches
On the model, the arena fighting area was 15.44 inches long, the wall around it was 10 inches wide and the wall was 0.83 inches tall.

4.
6/18=0.33 inches
The gladiators were, in scale, about 0.33 inches tall.